Cords v. Anderson
In Cords v. Anderson, 80 Wis. 2d 525, 259 N.W.2d 672 (1977), the supreme court held that a park manager had an absolute, certain or imperative duty to place warning signs or advise superiors of the conditions of a dangerous public trail. See Cords, 80 Wis. 2d at 542.
The manager knew that people regularly used the trail at night and that it passed a few inches from a ninety-foot gorge. See 80 Wis. 2d at 536-37.
The supreme court held that the park manager had a ministerial duty to erect signs warning of the obvious danger or advise superiors of the danger because there "can be no policy of leaving it alone when such an obvious danger exists." Cords, 80 Wis. 2d at 538.